Table 4.

Effects of the inhibition of different rumen microbial groups and of the supplementation of different oilseeds on total short-chain, C₂ and C₃ fatty acids.

Traits/oilseeds	Treatment					SEM	P-values
	Intact rumen fluid	–Archaea	–Fungi	–Protozoa	Only bacteria		Treatment	Oilseed	Interaction
Total short-chain fatty acid (mmol L−1 rumen fluid)						1.20	<0.001	<0.001	0.61
Control	87.4v	83.0cw	85.0cvw	76.5bx	74.6cx		<0.001
Safflower	90.9v	86.1abw	89.0abvw	77.5bx	77.1abx		<0.001
Poppy	92.7v	84.1bcwx	87.6bcvw	77.0bxy	75.0bcy		<0.001
Camelina	95.2v	88.1aw	90.8aw	79.8ax	77.7ax		<0.001
Mean	91.5v	85.3w	88.1w	77.7x	76.1x		<0.001
P-values	0.12	<0.001	<0.001	<0.001	0.005
Acetate (mmol mol−1)						4.7	<0.001	<0.001	0.76
Control	683v	626abx	657abw	588ay	569(a)z		<0.001
Safflower	674v	628aw	659av	581abx	567(ab)x		<0.001
Poppy	683v	632aw	661av	578abx	563(ab)x		<0.001
Camelina	671v	619bx	650bw	576by	553(b)z		<0.001
Mean	678v	626x	657w	581y	563z		<0.001
P-values	0.32	0.004	0.005	0.026	0.066
Propionate (mmol mol−1)						6.8	<0.001	0.011	0.89
Control	172x	213(b)w	203(ab)w	316(b)v	331bv		<0.001
Safflower	177x	216(ab)w	202(b)w	324(x)v	334abv		<0.001
Poppy	174x	217(ab)w	204(ab)w	325(a)v	336abv		<0.001
Camelina	178z	219(a)x	204(a)y	326(a)v	345av		<0.001
Mean	175z	216x	203y	323w	336v		<0.001
P-values	0.60	0.074	0.095	0.051	0.038
Acetate-to-propionate ratio (x:1)						0.088	<0.001	0.067	0.98
Control	3.99v	2.95ax	3.25abw	1.87ay	1.72(a)y		<0.001
Safflower	3.82v	2.92abx	3.28aw	1.80aby	1.71(ab)y		<0.001
Poppy	3.97v	2.92abw	3.26abw	1.79abx	1.68(ab)x		<0.001
Camelina	3.78v	2.83bx	3.20bw	1.77by	1.61(b)y		<0.001
Mean	3.89v	2.91x	3.25w	1.81y	1.68y		<0.001
P-values	0.56	0.028	0.020	0.030	0.056

^a–cWithin a column, means without a common superscript differ, P < 0.05; superscripts in brackets indicate a trend of a difference among means, P < 0.10.

^v–zWithin a row, means without a common superscript differ, P < 0.05.

SEM, the overall standard error of the mean.